package edu;

import java.sql.*;
import java.util.ArrayList;
import java.util.List;


    public class DataBase {

        public List<User>   getUserList(){

            List<User> userList = new ArrayList<User>();

            // 3+1
            try {
                Class.forName("com.mysql.jdbc.Driver");

                Connection connection = null;
                Statement statement = null;
                ResultSet resultSet = null;

                String sql = "select * from t_users";

                connection = DriverManager.getConnection(
                        "jdbc:mysql://localhost:3306/javaweb_2018?serverTimezone=UTC",
                        "root",
                        "195122"
                );

                statement = connection.createStatement();

                resultSet = statement.executeQuery(sql);

                while(resultSet.next()){

                    int id = resultSet.getInt(1);
                    String name = resultSet.getString(2);
                    String password = resultSet.getString(3);

                    // [封装]在user中
                    User user = new User();
                    user.setId(id);
                    user.setName(name);
                    user.setPassword(password);

                    userList.add(user);
                }
                // 数据库 -> List
                resultSet.close();
                statement.close();
                connection.close();

            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            } catch (SQLException e) {
                e.printStackTrace();
            }

            return userList;

        }
    }

